Owing to industrialization and urbanization, environmental pollution has emerged as a social issue for a long time, and accordingly, the control of water quality such as the protection of water supply sources and the management and regulation of pollutant discharge facilities becomes strict systematically on a national level. It is the basis of the control is to quickly and accurately measure the contaminants in water. Through rapid water quality measurement for raw water, purified water, and running water related to drinking water, an appropriate water purification process is applied, and therefore, the water quality measurement is very important in view of safety.
Organic contaminants, which are managed by a water supply system, include tens of substances such as volatile organic compounds, agricultural chemicals, disinfection by-products, taste and odor substances and so on. Because such organic contaminants give harmful effects on people's health or cause an aesthetic problem on the water containing them, they have a direct influence on the water quality, and accordingly, complete management for each substance of the organic contaminants should be required. Among them, the taste and odor substances (geosmin and 2-MIB) are increased in the concentration and frequency introduced in a water purifying plant due to the increment of algal blooms in a water supply source caused recently by climate changes like water temperature increases and rainfall pattern changes, and so as to rapidly treat the taste and odor substances before they are introduced into a water distribution network, accordingly, a water purifying material like powdered activated carbon has to be applied to the water purifying plant to allow the purified water to have a value less than an odor threshold value, thereby avoiding the complaints of consumers. Therefore, more careful management for the taste and odor substances should be needed.
The taste and odor substances are normally analyzed manually, less than once a day, in a water purifying plant, and if they are generated in high concentrations, they are analyzed twice a day. However, it is not easy to cope with rapid water purification process through the manual analysis of the water qualities varied from hour to hour. Further, the volatile organic compounds and agricultural chemicals are generated in small quantities on emergency situations like leakage accidents of chemical factories in a water supply system and rollover accidents of tank lorries carrying chemicals, but the disinfection by-products generated in the water purification process have to be monitored in real time. In this case, also, they are measured manually, so that it is hard to rapidly cope with them through rapid detection.
So as to solve the above-mentioned problems, endeavors for monitoring water quality in real time have been tried in conventional practices.
For example, various technologies for monitoring water quality in real time have been suggested in Korean Patent No. 10-0901779 (Jun. 2, 2009) entitled ‘internet-based monitoring and control system for measuring water quality’, Korean Patent No. 10-0522764 (Sep. 12, 2005) entitled ‘real-time water quality monitoring device and method for controlling the same’, Korean Patent No. 10-1406884 (Jun. 5, 2014) entitled ‘multi-wavelength analysis-based on-line water quality measuring system for real-time detection of organic contaminants in water’, and Korean Patent No. 10-1253251 (Apr. 4, 2013) entitled ‘real-time taste and odor substance monitoring and control device and method for water purification’.